基于干扰门限的动态频谱接入及性能分析  

Interference Threshold Based Dynamic Spectrum Access and Its Performance Analysis

作　　者：胡晗[1] 朱琦[1,2] 

机构地区：[1]南京邮电大学江苏省无线通信重点实验室,江苏南京210003 [2]东南大学移动通信国家重点实验室,江苏南京210096

出　　处：《南京邮电大学学报（自然科学版）》2010年第2期8-15,共8页Journal of Nanjing University of Posts and Telecommunications：Natural Science Edition

基　　金：国家重点基础研究发展计划(973计划)(2007CB310607);国家自然科学基金(60772062);东南大学移动通信国家重点实验室开放研究基金(N200813)资助项目

摘　　要：如何在不干扰授权用户(主用户)正常通信的情况下提高次用户使用频谱的效率,这是认知无线电系统中需要解决的关键问题。在主用户优先的基础上,提出了基于干扰门限的动态频谱接入系统的M arkov频谱占用模型,并基于该模型对动态频谱接入过程进行了分析。为了进一步降低次用户间的相互干扰,通过对次用户接入概率的设计,以协调各类次用户间的频谱接入。在3种优化准则下,对次用户依据概率接入的基于干扰门限的主用户优先的动态频谱接入系统进行了仿真。仿真结果表明,基于干扰门限的主用户优先的动态频谱接入系统能大大提高次用户的接入机会,最大程度地提高了次用户的吞吐量。在比例公平准则下次用户接入的性能,与最大化吞吐量准则相比体现了更好的公平性,与最大化最小准则相比能够获得更大的吞吐量,因此基于比例公平准则可以使得系统在高效性和公平性间得到很好的均衡。How to improve the spectrum utilization of the secondary users without interfering the primary spectrum holders＇ usage becomes a key issue in the cognitive radio system. A Markov spectrum occupation model is proposed for the dynamic spectrum access system based on interference threshold scheme. The process of the dynamic spectrum access is analyzed. In addition, to decrease the mutual interference among the secondary users, appropriate access probabilities for the secondary users are designed to coordinate the spectrum access of the secondary users. Using three kinds of optimization criteria, the proposed dynamic spectrum access system is simulated with the primary user taking priority and the secondary user accessing with propability. The simulation results have shown that the access opportunity of the secondary users is enhanced considerably and the overall throughput of the secondary users is improved greatly. With proportional fairness criterion, the proposed access system not only provides fair spectrum sharing among secondary users compared with the maximal-throughput criterion, but also achieves much higher throughput than the max-min criterion.

关 键 词：认知无线电 动态频谱接入 马尔可夫模型 干扰门限 

分 类 号：TN929.5[电子电信—通信与信息系统]